tattoogoddess wrote:That is my plan! Stocking up on lights! Have not seen any battery powered ones though I think I need to look to find a pack that I can plug my lights into. Any leads? I just want to do it for my bike.

Any place that has a large selection will have some battery set ups.. You have to REALLY LOOK hard for them though. big-box hardware even. even saw solar rope lights now.

BBadger wrote:Dang, I was going to suggest some of those power sticks at ExtremeGlow, but they don't sell them anymore. They were great for lighting up bikes with. The other cheapo light sticks work though.

BBadger wrote:Dang, I was going to suggest some of those power sticks at ExtremeGlow, but they don't sell them anymore. They were great for lighting up bikes with. The other cheapo light sticks work though.

No, the "Power Sticks" like these. They used to be part of that category, but the sticks were larger and held AAA batteries as opposed to those button cells. I was initially disappointed with them, but they did make great bike lights for visibility purposes. EG had them last year, but maybe they sold out or something.

I'm a pretty big fan of these though. Though they're pretty obnoxious because of the blinking. They also suck for not having an off switch. Unscrewing them often leads them to fall apart too Still, the light pipe on them is really quite nice and they're well built.

"The essence of tyranny is not iron law. It is capricious law." -- Christopher Hitchens

BBadger wrote:No, the "Power Sticks" like these. They used to be part of that category, but the sticks were larger and held AAA batteries as opposed to those button cells. I was initially disappointed with them, but they did make great bike lights for visibility purposes. EG had them last year, but maybe they sold out or something.

Ahh.. I gotcha. They look just like the led swords which do make great cheap lightup material. We had a couple of nights without the lightsuit where I just stuck one in the webbing of my backpack with the top about head high and it worked fine for safety. $1.50 and you can't really go too wrong.

You know.. I can only hope to dear god that my LED company gets talked about as much as EG does on here.. geez.

It will power them, but they may not last very long. Based on that math, they will run about 3 hours.

Are you planning on having them flash, or be steady burning? You start to run into variables with flashing lights...the longer they are "off" the longer your battery will last...it can be difficult to calculate.

The controller probably has some current draw as well, which will reduce the life as well.

There are many options...depending upon your resources on playa (generator for recharging?) and your financial resources (Li-Ion batteries are great...good mAh ratings, charge fast, but are expensive!)

I am thinking about getting a belt pack and putting 2 lantern style batteries, in series. They are 6 volts each, and a whopping 13,000 mAh each! They should last all night, and then just throw them away. Last thing you want to have happen is forget to charge your batteries...then your glorious project that you spent so much time on will just be a hat.

There are several things wrong with your math. First, if you are running batteries in series, the amps don't get multiplied with the number of batteries. So you would have to draw 6 Amps out of each Battery. I am not sure what the max is for AA, but I doubt they could even deliver 6 Amps.

Second, what is that 2400mA number? That sounds like it could be the capacity of a AA. In that case it's mA/h (milliAmp/Hours), not mA. Which means you can't multiply that by 8 and get anything meaningful.

Depending on weather you put your batteries in parallel or in series, you would either get 2400mA/h at 12V, or 19A/h at 1.5V, but not both.

Theoretically, if you could draw 6A from a battery that has a capacity of 2400mA/h, it means the battery would lasst 24 minutes. In reality it would be even less, since the capacity it not a set constant, but depends on how much power you are drawing. The faster you discharge the battery, the less you are going to get.

OTOH, as DustHand pointed out, it depends on the program you are running on your LEDs. Are they all on all the time, or are you running some kind of pattern? So you should probably figure out what effects you are running on it, then measure how much current they draw under those circumstances, then work you way to the battery requirements from there.

On the second page, check out the "Typical Delivered Capacity vs Power Drain" chart. Over 100mW (=66mA) you are seeing the capacity droping noticably. At 500mW (=333mA) you are getting less than half of the capacity, and over that it just falls of a cliff. No way are you getting 6 Amps.

You're going to put five (5) meters (~16ft) of LED rope on your hat and expect to power them for long using common household AA batteries? The hat will look cool, but AAs won't cut it. You need to know how to power them properly.

- Understanding batteries:

- Batteries are theoretically able to provide infinite current. What you're most interested in besides voltage is the amp-hour (AH) rating, i.e. how long the batteries can supply a given amount of current. Alkaline AA batteries, for example, have a mAh (milliamp-hour, i.e. 0.001Amp * hour) rating of about 2600mAh maximum--at a 500mA loads. For a perfect Alkaline battery (most are not 2600mAh), or rather 8 of them to make 12V, you'd get about 26 minutes of light at 6Amps (2600mAh = 2.6AH --> 2.6AH / 6Amp = 0.43hours = 26 minutes). This will not be the case in practice, see below:

- Some batteries are better for some things than others:

Alkaline batteries have long shelf-life at low current drain and hold their voltage high until they're almost completely discharged; they're great for regular flash lights, smoke detectors, etc. They are not good at high discharge (current) rates, because high discharge rates causes heating and internal resistance, reducing battery life substantially.

Deep-cycle lead-acid batteries are great for high-current power solutions; they're also cheap for their AH ratings, but heavy because of the lead and chemicals. Deep-cycle means it can be (re)charged and discharged many times without reducing capacity, which makes them popular for solar cell array power storage, and large power capacity storage. They are great for camp lights if you can keep them charged (don't discharge below 50% for long life, and use a special charging circuit).

Nickel-Metal Hydride (NiMH) rechargeable batteries are good high-current-drain rechargeable batteries, often used as replacements for consumer Alkaline batteries, but have slightly lower voltages than Alkalines (1.2V vs. 1.5V), and have self-discharge over time. NiMH batteries are great for digital cameras and RC vehicles (for motor power) because they support high current drain (and good for your LEDs too), but due to their weight are not good (ideal) for portable devices or RC aircraft.

Lithium-Ion (Li-Ion) or Lithium-Polymer (Lipo) rechargeable batteries pack the highest energy density of all rechargeable batteries, have higher voltages (3.6-4.2V), but are expensive, must be charges with special circuits lest they burn or explode, and need to be conditioned initially for long lifespans; they're good for portable devices and applications needing a lot of energy, but are expensive.

Nickel-Cadmium batteries are the rechargeable batteries of the olden days, notorious for their "memory effect" which artificially reduces capacity if you don't continuously condition your batteries. Don't buy these.

- What should you get? I would suggest buying some RC battery packs (like these). Yes, they're expensive, but it's because they're rechargeable. That other battery thread describes using D-cell batteries. That's great, but those are usually Alkaline batteries, and despite the size and capacity of D-cells, they will suffer from heating and high discharge, which reduces their mAh rating. Those D-cells also expensive at about $1.20 each I believe. RC battery packs are usually made with NiMH batteries, which are perfect for high-drain applications such as the lighting you're planning.

- What else should you do? You should sequence your LEDs (i.e. program them to turn on and off) if possible, in order to not have them on all the time. Even with a big-ass battery pack, you'll only get a few hours at most out of them running at a full 6Amps, unless you want a carry around a couple 100-pound lead-acid batteries in a backpack. Those 5meter ropes are VERY bright, especially at night. They're the same brightness as those LED strip lights on the Tunnel of Questionable Enlightenment. You don't need them at full brightness, and you should look into a dimmer.

For rope lights, I would suggest you buy some of those programmable LED rope lights. Then you can program in patterns, which will save you power, and also look cool. You'll still need the 12V battery packs, and those strips of lights cost a pretty penny (look for those using the WS2801 driver). Oh, and you need to program them, but you can search the board for tips on that.

"The essence of tyranny is not iron law. It is capricious law." -- Christopher Hitchens

tattoogoddess wrote:Head up, not sure if your dollar general has them in your area but they have them here- 150 hour ECO LED glow sticks for $2. The ones with the little batteries from LifeGear. They are bright!! They have them on their site for $2.99. They have one with a flashlight,whistle, and the led with 200 hours for $6.99 and the waterproof one for $9.99

I picked one up and am thinking about picking up the last 3 that where there tomm. Pretty good deal!! I got blue/teal. Turned it on in the dark and it actually kinda hurts my eyes.

Just found out about these searching online for eco-friendly glow sticks. So exciting! Fellow Canadians, they have 'em at Canadian Tire (finally figured this out after determining that none of the retailers that carry them in the States seem to sell or ship them here). Such a great idea! Will be useful for BM, camping, and mini-light-sabre (light dagger? light switchblade?) battles.

If you want drama to stop following you everywhere, try letting go of the leash.